An epic showdown is shaping up between Donald Trump and Hillary Clinton.

In most of the Super Tuesday presidential primaries and caucuses, Trump and Clinton won decisive victories, building critical momentum for their campaigns.

There were a few exceptions. In the Republican contests, Ted Cruz won Alaska, Oklahoma and his home state of Texas. Marco Rubio won Minnesota in his first victory of the campaign and John Kasich finished a close second to Trump in Vermont. In the Democratic race, Bernie Sanders carried Oklahoma, Colorado, Minnesota and his home state of Vermont.

But overall the map was dominated by Clinton and Trump as each carried seven states.

Clinton had plenty to celebrate on Super Tuesday.REUTERS/Jonathan Ernst

Super Tuesday essentially locked up the Democratic nomination for Clinton. Sanders will stay in the race as a protest candidate, winning a state here and there, but Clinton now has an insurmountable lead in the Democratic delegate race.

Trump’s ambiguous position on the KKK did not seem to trouble Republican voters on Super Tuesday. He carried most of the southern states by comfortable margins and he won his biggest victory in Massachusetts, which he carried by 30 points.

A Republican civil war

The most striking feature of Trump’s Super Tuesday victories was the fact that he carried states as different as Massachusetts and Alabama. He has a large lead in the delegate race and the national polls now put him at 49 percent support among Republicans, his best showing ever. Trump is clearly within striking distance of the GOP presidential nomination.

Trump’s policy positions make a mockery of cornerstone principles of the modern Republican Party. For years conservativeRepublicans have stood for free trade, tax cuts, limited government, business deregulation, religious freedom, military interventionism, the containment of Russian power and an expansive view of free speech rights.

Trump rejects almost all of that. His political success shows that orthodox conservative ideology no longer resonates with the GOP base. As the nomination comes within the billionaire’s grasp, Trump’s right-wing populism makes him the greatest threat that American conservatism has ever faced.

That’s why war is looming. The conservative power structure will not go down without a fight. Conservative intellectuals have overwhelmingly condemned Trump, including George Will, Michael Gerson and the editors of the leading conservative magazine National Review. So too have Republican leaders such as South Carolina Governor Nikki Haley, Nebraska Senator Ben Sasse, House Speaker Paul Ryan and former GOP nominee Mitt Romney.

Although the Republican civil war will be a fascinating spectacle to watch, the Super Tuesday results suggest that the conservative attack on Trump is simply too little, too late.

At this point, the GOP’s civil war is a war that Trump is likely to win.

Clinton leads a united Democratic Party

The atmosphere could not be more different on the Democratic side.

Although rank-and-file Democrats express very little passion for Hillary Clinton, the Super Tuesday results make clear that Democrats are closing ranks behind her campaign. She has a commanding lead just three short weeks after her stunning defeat in New Hampshire.

How did Clinton turn things around so quickly and decisively?

First and foremost, she crushed Sanders among African-American voters, the heart of the Democratic Party. In South Carolina, for example, Clinton carried 84 percent of African-American voters. Since the Democratic Party embraced civil rights in the 1960s, African Americans have been the party’s moral center. You cannot win the Democratic nomination without the backing of the African-American community. Sanders’ inability to make inroads with black voters has proven a fatal flaw in his candidacy.

Economic realities also undermined Sanders. Liberal economists ridiculed Sanders’ education and health care proposals as unrealistic and unworkable. The fundamental problem was that Sanders’ proposed tax hikes would never produce enough revenue to fund the trillions of dollars he proposed in additional spending. Former top Obama economist Austan Goolsbee bluntly warned fellow Democrats that “the numbers don’t remotely add up” in Sanders’ policy proposals. The attack from the left dealt a body blow to the Vermont senator’s effort to present himself as a serious national candidate.

Third, the specter of a potential Trump presidency dimmed Democratic enthusiasm for Sanders. Although the prospect of a far left-wing Democratic nominee understandably inspires liberal dreams, most Democrats realize Sanders would not fare well in a general election since only 24 percent of the electorate is liberal. With Trump leading the Republican field, Democrats have little stomach for nominating a high-risk candidate of their own.

The result is that Clinton essentially has the nomination wrapped up.

The most pressing issue she must get behind her now is the FBI’s investigation into her handling of classified emails during her time as secretary of state. As Clinton turns her focus to the general election, the email scandal is a more serious threat to her than the Vermont senator’s fading campaign.

2016 election will be divisive

Clinton and Trump are two of the most polarizing figures in modern political history. If, as is likely, they win their parties’ nominations, voters in November will face a choice between a scandal-plagued Democratic nominee and a demagogic Republican nominee.

Clinton will clearly be the favorite to win, particularly in light of the GOP’s internal divisions and Trump’s toxicity. But if the primaries and caucuses are any guide, the general election will be volatile, divisive and highly unpredictable.